1. Field of the Invention
The present invention relates generally to a system for puncturing pressurized containers such as relatively thin-walled aerosol spray cans, for emptying contents therefrom, for collecting liquid contents for environmentally safe disposal, and for filtering vapor-laden propellant gas to remove environmentally objectionable constituents therefrom so that the remaining gas safely can be vented to atmosphere. In preferred practice, the present invention relates to methods and apparatus features of a system 1) that is capable of being used with all known "standard" sizes of aerosol spray cans, 2) that employs ergonomically designed lever-operated clamping and piercing mechanisms to clamp and pierce bottom walls of aerosol cans that are guide-centered at a workstation, 3) that ducts contents from pierced aerosol cans into a collection receptacle where liquid is retained, 4) that draws vapor-laden propellant gas out of the collection receptacle and through a series of filters before discharging it into a reduced-pressure plenum for eventually being vented to atmosphere, and 5) that entrains in a flow of ambient air that is ducted into the reduced-pressure plenum such gas emissions as may inadvertently emanate from the vicinity of the workstation.
2. Prior Art
Thin-walled pressurized containers such as aerosol spray cans are used in homes and in industry to spray a wide variety of active ingredients such as paint, lubricant, furniture polish, air freshener, deodorant and the like by discharging the active ingredients as a vapor that is entrained in a flow of propellant gas. When the supply of active ingredient carried by an aerosol spray can has been substantially exhausted; when an aerosol spray can fails to properly function in providing a suitable spray-type discharge of active ingredient; and/or when an aerosol spray can is found to be damaged, improperly assembled or inappropriately filled with active ingredient or propellant gas, it is desirable to properly process the aerosol spray can for disposal by safely puncturing the can to relieve the pressure therein, to empty contents therefrom, to collect liquid contents therefrom, and to filter vapor-laden propellant gas before permitting the filtered gas to be released to atmosphere.
To permit a plurality of aerosol cans to be safely punctured and emptied with at least a portion of their contents being collected and/or filtered, a variety of puncturing devices that duct contents to collection receptacles have been proposed. Some of these proposals utilize one or more filters through which gaseous contents emanating from the collection receptacles are permitted to pass before being vented to atmosphere.
While some of these proposals are intended to provide relatively simple, relatively inexpensive manually operable units for piercing aerosol cans, for collecting liquid contents, and for filtering gaseous contents, the proposals made to date tend to be characterized by one or more drawbacks such as a failure to provide a system that is readily adjustable to accommodate all known "standard" sizes of aerosol spray cans, that is ergonomically designed to be easy to operate while processing a plurality of aerosol cans for disposal, that does an effective job of assuring that vapor-laden propellant gas is suitably drawn away from the vicinity of a workstation where cans are punctured, and of filtering environmentally objectionable constituents from released gases.
To the extent that manually operated puncturing units have been proposed that are intended to be mounted atop a lid of an upwardly opening collection container, such proposals typically have been characterized by one or more of the drawbacks mentioned above, and/or by one or more of the drawbacks that are described below.
Some proposals provide a closable chamber into which an aerosol spray can is to be inserted, with the entire interior of the chamber and the entire exterior surface of an aerosol can that is positioned in the closed chamber being subjected to a cloud of liquid, vapor and propellant gas that discharges from the aerosol can when the aerosol can is punctured. Such an arrangement renders quite messy the business of reaching into the chamber to retrieve an emptied aerosol can, and causes unwanted coating of substantially all exterior surfaces of the cans that are to be disposed of, whereby far less than the desired quantity of contents discharged from punctured cans tends to be collected for environmentally appropriate disposal.
Some proposals utilize a poorly supported resilient sealing member both to effect a vapor-tight seal about peripheral portions of the lower part of an aerosol can, and to support the downwardly-clamped aerosol can during a puncturing operation. The substantial loads that are imposed on the resilient sealing member, and the poor manner in which the resilient sealing member is supported combine to contribute to rapid deterioration of the resilient sealing member, whereby its sealing capability tends to be significantly diminished if not entirely defeated after being used to receive, support and seal with a relatively small number of aerosol cans during the time while they are being pierced and emptied.
As more and more small business entities are being called upon to assure that aerosol spray cans are disposed of in an environmentally suitable manner, the long-standing need for a simple to use, relatively inexpensive and reliable system to permit one or more aerosol spray cans to be disposed of from time to time has grown more urgent and has not been found to be satisfactorily addressed by prior proposals.